Among the state-of-the-art printed circuit board techniques, a flexible printed circuit (FPC) is the most promising one, which features light weight, small volume, dynamic flexibility, and resilient deformability and is fit for various assembling conditions for products of all types of outside configurations for providing characteristics of increasing lay-out density of wiring and flexibility of bending to serve as a circuit carrier for signal communication and/or coupling of components. Since an FPC can be connected with active and passive components or modularized devices, the FPC also possesses mechanical features.
In the past decade, the FPCs have been widely applied to various system products, especially thin and light-weighted electronic products. For example, consumer electronic products, such as mobile phones, digital cameras, computer peripherals, flat panel displays, and game devices, all find application of FPCs. Besides being endowed with a high growth rate in the field of panel displays and consumer electronic products, technology that employs FPCs as medium of transmission also makes a great and un-erasable contribution to the development of the electronic industry.
The FPCs often serve as signal connection means in a foldable and/or rotatable part of an electronic device. The most commonly known application of the FPC is found in a hinge part of an electronic device, such as clamshell devices, slip devices, flip devices, and even three-dimensional rotation devices, which contribute the greatest product value to the application of the FPC in electronic devices. With the fast development and change of technology, the outside configuration and the function-related designs of electronic devices get diversified, so that the structural design of the FPC must be versatile.